Koopa gets another present for Kootie Pie - this time he plans to use his Doom Sub to chase everyone out of Venice, Italy then warp the entire city to Dark Land so Kootie Pie can have her own water park. The Mario Bros. are approached in Desert Land by an Italian gondolier and since Mario has a passion for the country of Italy, they couldn't resist. Armed with Frog Suits, can they stop Koopa in time?

Kooky has developed a pendant for King Koopa that will grant him the powers of the Mario brothers, but it can only be used in the real world. Koopa uses that to his advantage and lures his unsuspecting enemies into the real world using Luigi as bait. But the Princess manages to contact Toad, who races to get as many power ups to the Mario brothers in time.